1. Field of the Invention
The present invention relates to a liquid crystal display, and more particularly to a device for driving a liquid crystal display having an improved control signal transmission system between a timing control IC and a driving IC.
2. Description of the Prior Art
As generally known in the art, in order to drive a liquid crystal display (LCD), a drive IC, a timing control ASIC, and an analog circuit should be provided in the corresponding LCD panel. The timing control ASIC serves to receive an RGB signal through a host interface, distribute data to a source driving IC, and a control gate driving IC.
Main control signals generated by the timing control ASIC for the purpose of controlling the source driving IC are a carry signal STH for informing the source driving IC of the start of data, a signal POL for reporting the polarity of an output voltage, a signal LOAD for reporting a latch and output of data, etc. Also, main control signals generated by the timing control ASIC for the purpose of controlling the gate driving IC for driving TFTs are a carry signal STV for informing the gate driving IC of the start of data, a clock signal CPV for driving the IC, and an output control signal OE.
In the control IC of a TFT LCD module, video data and control signals of a pixel driving IC are transmitted in the form of a bus on a printed circuit board (PCB). In this case, it requires a technique having a very high degree of difficulty, designing 36 to 48 image data lines and 10 control signal lines. Especially, due to the development of gates without PCB, wiring to the gate driving IC requires a high degree of difficulty since it should be prepared as a pattern on glass.
The data of the existing LCD driving IC includes basic image data and data for processing various signals, and it is necessary to reduce the data. Especially, as the resolution and data bits increase, the reduction of signals is necessary for an optimum design of the PCB.